The present invention is generally drawn to a comparator driven by a transconductance amplifier. More specifically, the present invention is drawn to a DCDC converter including a comparator driven by a transconductance amplifier.
A DCDC converter is an electronic circuit that converts a source of direct current (DC) from one voltage level to another. One conventional type of DCDC converter includes a transconductance amplifier, whose output is used as one of the inputs to a comparator. The other input of the comparator is based on the output voltage generated by the DCDC converter.
In some conventional DCDC converters that include a transconductance amplifier-driven comparator, the comparator input includes a complimentary differential pair, wherein a pair of p-channel field effect transistors (p-FETs) and a pair of n-channel field effect transistors (n-FETs) are used. Such a comparator is very complex, requires a relatively large amount current for biasing, larger silicon area and has a complex transfer function in the middle range of operation.
In some other conventional DCDC converters that include a transconductance amplifier-driven comparator, the comparator input includes a differential pair of p-FETs. These types of DCDC converters support operation close to the lower rail of the comparator.
What is needed is a DCDC converter that includes a transconductance amplifier-driven comparator that does not have the disadvantages of the conventional systems discussed above.